Pesquisa de anticorpos IgG para Neospora caninum e avaliação dos fatores de risco em ovinos do Estado de Sergipe

Abstract

The aim of this study was to determine the occurrence of antibodies IgG against Neospora caninum and evaluate the risk factors associated with the infection in ovine herds, State of Sergipe, Brazil. Blood samples (n=1200) were collected from sheep raised in 60 sheep run located in the three mesoregions of the State of Sergipe, between 2011 e 2012. Antibodies were investigated by Indirect Immunofluorescence Antibody Test of which cutoff point was 50 and positive samples were diluted in base 2 until the last positive titer. Data from 15 variables was obtained from questionnaires given to farmers. Absolute and relative frequencies were determined and the risk factors were analyzed by Pearson's Qui-Square test (p≤0,05). The occurrences of serum reactive sheep were 39.83% (478/1200). The occurrences of positive sheep and sheep run were 55.88% (380/680) and 88.24% (30/34) in the Eastern region; 21.42% (60/280) e 42.85% (6/14) in dry region and 15.83% (38/240) e 41.67% (5/12) in the backwoods respectively. Antibody titers ranged from 50 (n=459), represented 96.02% (459/478) of seropositive samples to 6400 (1/478). Among the significant variables in the multivariate analysis were considered risk factors for infection with N. caninum were, sheep run located in Eastern region (p=0.000, OR=4.64, CI95%=3.36-6.41); standing and running water sources (p=0.000 OR=2.03, CI95%=1.41-2.92), absence of quarantine (p=0.000, OR=2.71, CI95%=2.08-3.53), absence of dunghill (p=0.000, OR=3.14, CI95%=2.45-4.02), presence of dogs (p=0.000, OR=2.74, CI95%=1.73-433), presence of wild animals (p=0.000, OR=3.45, CI95%=2.44-4.87) and subsistence (p=0.000, OR=4.99, CI95%=3.15-7.92) or reproduction (p=0.002, OR=1.74, CI95%=1.22-2.49) livestock were important risk factors. Our results highlight the occurrence of N. caninum in the ovine herds from State of Sergipe. Management and location of sheep runs were important risk factors associated to the infection.INDEX TERMS: Neospora caninum, infection, parasite, sheep, risk factors, indirect fluorescent antibody test.

Seroprevalence and risk factors associated with Neospora caninum in commercial sheep from northwest of Rio Grande do Sul, Brazil

“…The failure to identify a common starting time for illness may also have led to bias (Choi & Pak, 2004). In the state of Sergipe, a prevalence (39.8%) higher than that found in this study was observed; associated risk factors included water source, absence of quarantine, and the presence of dogs and wild animals (H. Rizzo et al, 2017). These results were possibly due most likely to exposure to food or water contaminated with N. caninum oocysts eliminated by dogs.…”

“…Additional factors associated with neosporosis in sheep include water source(s), absence of quarantine, and farm size and system of production (Faria et al, 2010;Rizzo et al, 2017). Compared with previous studies, no association was found among these variables.…”

“…Neospora caninum infection can lead to spontaneous abortion or the birth of weakened lambs (Moreno et al, 2012;Razmi & Naseri, 2017). Its prevalence in Brazilian herds ranges from 8% in São Paulo (Machado, Kikuti, Langoni, & Paes, 2011) to 39.8% in Sergipe (H. Rizzo et al, 2017). However, its clinical and economic impact on sheep is not fully understood, with few, if any, published studies in the surveyed region.…”

Characterization of goat and sheep production in the state of Sergipe, Northeast of Brazil

“…These animals can act as reservoirs of zoonotic infectious agents. The existence of dogs and cats in farms in Sergipe has already been determined as a significant factor associated with infection by Toxoplasma gondii (RIZZO et al, 2017a) and Neospora caninum (RIZZO et al, 2017c) in the sheep flocks in the State. Inadequate sanitary measures can lead to the access of dogs and cats to the viscera, placenta remains, and miscarriage products from infected animals, favoring, through contamination of water and food sources, the spread of two agents in the herd, the oocysts Toxoplasma gondii and Neospora caninum.…”